Help with Breast Screening Guidelines
Breast Screening Guidelines for women in the 40s have gotten more confusing. For women at low-to-average risk of developing breast cancer.
- The American Cancer Society now recommends screening mammograms every year from age 45-54, and every other year for women 55 years and older.
- The American Congress of Obstetrics and Gynecology still recommends that all women in their 40’s have annual screening mammograms.
- The US Preventive Services Task Force , American College of Physicians and the American Academy of Family Physicians feel that the decision to start mammograms before age 50 should be individualized based on a woman’s personal risk, her values, and the potential benefits and harms of screening.
Why would anyone recommend woman not get screened for breast cancer starting at 40? Because screening has harms as well as benefits.
Imagine that 10,000 women have annual mammograms for 10 years, starting at age 50. There are six potential outcomes. According to an analysis published in JAMA, most will receive a false positive. 6,130 women will get called back for more testing for something ultimately deemed not to be cancer. Of these 940 will have an ultimately unnecessary biopsy. Another 3,568 women will have only normal, or “clean,” mammogram results over the course of that decade. Finally, 302 women will be diagnosed with breast cancer. Out of those women, 173 will survive the cancer, regardless of whether they were screened; 62 of them will die despite the screening; 57 women will be diagnosed with a cancer that would have never hurt them; and 10 women will avoid dying of breast cancer, possibly because they got a mammogram. So those 10 lives saved, though wonderful, have a cost in time, testing, worry and overtreatment. Is it worth it? Probably yes, but for some, perhaps the costs are too high.
Now the earlier woman start screening, the more the harms start to outweigh the benefits. Women younger than 50 have fewer lives saved and more false positives, and more of them face overdiagnosis. Now your individual risk may vary. This site can help you find your personal risk: http://breastscreeningdecisions.com/ It’s a good tool, but unfortunately the site does not show the number harmed by overdiagnosis. These numbers are better illustrated in the graph from JAMA- Breast Cancer Screening: Benefits and Harms.
Now some believe new digital technology will give better results, but the current evidence is insufficient to assess the benefits and harms of digital 3-D mammography.